1. Field of the Invention
The present general inventive concept relates to a stereo sound generation system, and more particularly, to a method and apparatus to reproduce an expanded sound using a mono speaker and a stereo sound generation system employing the sound reproducing apparatus.
2. Description of the Related Art
Generally, a mono speaker is used to reproduce a stereo sound or a mono sound as an expanded sound.
Japanese Patent Publication No. 2004-104296, registered on Sep. 6, 2002, discloses such a sound reproducing apparatus for a mono speaker sound.
FIG. 1 illustrates a conventional expanded sound reproducing apparatus. Referring to FIG. 1, first and second buffers 3 and 4 of the expanded sound reproducing apparatus control the signal level of two channels L and R. A subtractor 5 subtracts the signals of the first and second channels output from the first and second buffers 3 and 4. A low-pass filter 6 (LPF) passes only a low frequency band with respect to the difference signal output from the subtractor 5. A third buffer 7 controls the level of the signal output from the LPF 6. An adder 8 adds the signal output from the third buffer 7 and the signals of the first and second channels. A fourth buffer 9 controls the level of the signal output from the adder 8.
Accordingly, the sound reproducing apparatus of FIG. 1 extracts only the low frequency band signals with respect to the difference signal between the two channels and adds the input signals of the two channels.
However, the conventional sound reproducing apparatus of FIG. 1 only controls the frequency band, and thus the sound diffuseness is not intensive. Moreover, the sound diffuseness with respect to the mono signal is remarkably low.